Assessment of Genetic Diversity in Brassica juncea (L.) Varieties by Using SCoT and CCMP Markers

Genetic diversity study was carried out in 15 varieties of Brassia juncea by using Start Codon Targeted (SCoT) and Consensus Chloroplast Microsatellite Primer (CCMP) markers. Total genomic DNA was extracted from young leaves following the standard CTAB method. A total of 36 SCoT primers and 10 CCMP primers were used for the analysis. The analysis revealed 51.98% and 60% polymorphism for SCoT and CCMP, respectively. Similarity coefficient was used to detect the phylogenetic relationship; subsequently dendogam was constructed for SCoT and CCMP data. SCoT analysis revealed that variety number 12 is most polymorphic. In SCoT analysis, the polymorphic primers amplified 252 bands, of which 131 were found to be polymorphic, resulting in a polymorphic frequency of 51.98% and an average of 4.67 polymorphic bands per primer. The polymorphism was maximum (85.70%) with primer SCoT 5, and was lowest (11.1%) with primer SCoT 11. Ten CCMPs were used to study genetic diversity in B. juncea varieties. Of these, 7 primers gave amplification products. The polymorphic primers amplified 15 bands in total, of these 9 were polymorphic resulting in a polymorphic frequency of 60% and an average of 1.28 polymorphic bands per primer. The polymorphism was maximum (100%) with primer ccmp3 and lowest (0%) with ccmp2, ccmp4, ccmp6, ccmp7, ccmp8 and ccmp10.